1. Field of the Invention
The present invention relates to an information processing apparatus, a processing method therefor, and a non-transitory computer-readable storage medium.
2. Description of the Related Art
Measurement apparatuses that measure the three-dimensional shapes of objects are known. Such measurement apparatuses are widely employed for, for example, component inspection in the industrial field and measuring the shape of a living body in the medical field. A measurement apparatus that uses a noncontact measurement method is especially effective when a target object may become deformed or damaged by a contact measurement method.
To measure a three-dimensional shape in a noncontact manner, a scheme that performs triangulation using an image captured by an image capturing apparatus is widely employed. In a technique described in, for example, Japanese Patent Laid-Open No. 2008-276743, a projection apparatus projects multi-slit light, to which a reference line pattern is added, onto an object, and an image capturing apparatus captures an image of the light reflected by the object. Thus, the three-dimensional shape is measured. More specifically, multi-slit light in which fine lines are aligned in parallel is projected as a measurement line pattern, and a reference line pattern with a feature added to the interval between the lines of the multi-slit light by changing their widths is projected. Using the feature of the reference line pattern, the two-dimensional position on the projection pattern and that in the captured image are associated with each other. Based on the result of association between these two-dimensional positions, respective lines which form the multi-slit light are associated with each other, and the three-dimensional shape is measured using triangulation by a light-section method.
In the above-mentioned technique, the reference line pattern added to the interval between the lines of the multi-slit light is generated by a pixel array with a relatively small area. It is very difficult to discriminate such a small-area pattern from noise in a captured image with a low S/N ratio.
In such a technique, a certain area must be allocated to the reference line pattern, so it is difficult to obtain multi-slit light with a relatively high density, thus making it impossible to accurately perform three-dimensional measurement of small objects.